Arch Linux

asmarks

Member

Registered: 2010-09-26

Posts: 3

KMS not working with ATI HD5770

After a new install, my computer hangs after booting with grub unless I disable kernel modesetting by adding "nomodeset" to the kernel boot line. (And I need KMS so that I can use the ati driver).

$ lspci | grep VGA
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Juniper XT [Radeon HD 5770]

dand91

Member

Registered: 2016-08-12

Posts: 1

Re: KMS not working with ATI HD5770

I'm not sure if you figures this out, but it may help someone else. I added "radeon.pcie_gen2=0" as a kernel parameter, and it started working for me. I'm on a 5770 like you. It looks like it may be a PCIE 2.0 issue

https://wiki.archlinux.org/index.php/AT … Parameters
"Since kernel 3.6, PCI-E v2.0 in radeon is turned on by default.
It may be unstable with some motherboards, deactivation can be done by adding radeon.pcie_gen2=0 as a kernel parameters."

I hope this helps!